Fix missing argument on sprintf

When I activate the plugin, my php error log has many warnings.

~~~
PHP Warning:  sprintf(): Too few arguments in /path/to/wp-content/plugins/take-notice/includes/class-take-notice-plugin.php on line 89
PHP Warning:  sprintf(): Too few arguments in /path/to/wp-content/plugins/take-notice/includes/class-take-notice-plugin.php on line 104
~~~

My commit stops those warnings and now a meta box on the edit page shows form labels correctly with post types and taxonomy names.